A1 = "12.1.1-13.12.31"
B1 =ROUND(DAYS360(DATEVALUE(SUBSTITUTE(LEFT(A1,FIND("-",A1)-1),".","-")),DATEVALUE(SUBSTITUTE(RIGHT(A1,LEN(A1)-FIND("-",A1)),".","-")))/30,0)
=DATEDIF(SUBSTITUTE("20"&LEFT(A1,FIND("-",A1)-1),".","-"),SUBSTITUTE("20"&RIGHT(A1,LEN(A1)-FIND("-",A1)),".","-"),"y")+1